[MENTION=99817]chaochou[/MENTION] - I think my group play a very vanilla narrativism. I say "vanilla" for two reasons. First, we use pretty mainstream system - Rolemaster, and now 4e - which don't have very complex narrativist mechanics (and therefore give the GM more of a role in using the mechanics to push one way rather than another, I think). Second, we don't talk about this self-consciously - my players (with one exception) like to build backstory for their PCs, which I then use to build situations around, and back-and-forth in a situation-leads-to-play-leads-to-new-facts/orientation-leads-to-new-situation fashion.
A third thing that makes our narrativism pretty vanilla is that we're pretty conservative on the techniques front. THe personnel of the group has changed a bit over the years, but the general tone hasn't. We've had serious wargamers, Australasian M:TG champions, a couple of guys who dominated the Melbourne PBM scene for many years - and so tactical play of the RM or 4e variety is a big part of our game. I run the occasional flashback or dream vignette, but nothing very radical.
The GMing approach is scene framing that would be regarded as pretty soft at The Forge, I think, but probably on the harder side for D&D play. (4e is a lot easier for this than Rolemaster!)
Backstory authority is mostly with me as GM, except for those bits of the world which immediately touch on the PCs, which they have control of. (And which they can call on to advantage in a way that is done informally rather than via Fate Points or similar eg "The merchant has probably heard of my uncle who used to trade in these parts, hasn't he" or "I give the secret hand signal of my cult to see if the Elvish captain recognises it" - in the latter case, I decided that the captain didn't, but a lesser member of the Elvish band did.)
Non-railroading in action declaration and action resolution is, for me, the single most important GMing principle I follow. This is what allows for player-driven play.
As far as the thematic focus, it's the sort of stuff that can be done in mainstream fantasy in which combat is the locus of conflict - so struggles over various philosophical or political/moral ideals, plus more local/low key stuff around PC loyalties/honour.
The last campaign was a RM Oriental Adventures game. The PCs included some samurais from a defeated clan, some monks, and an animal spirit banished from the heavens. The game was mostly about loyalty and karma - the PCs ended up defying the heavens to reshape the karmic destiny of a couple of exiled gods, and thereby of the mortal world.
The current, 4e, campaign, is still evolving, but similar themes are in play about the burdens of history. The drow chaos sorcerer/demonskin adept wants to defeat Lolth and undo the sundering of the elves. There are worshippers of the Raven Queen and Vecna who have various attitudes to fate and death. And there is a dwarf PC who is focused on rising above unpropitious beginnings (in my game, the dwarves, after escaping the giants, ended up under the tutelage of minotaurs).
And just in case you're not asleep yet from boredom - I've got some actual play posts
here,
here,
here and
here.